This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A243361 #9 Apr 25 2025 15:07:15 %S A243361 1,12,13,124,15,1236,17,1248,139,1125,111,1122346,113,11247,11355, %T A243361 112468,117,1123689,119,112245,11237,111222,123,1122234468,1255, %U A243361 112236,12379,11224478,129,111233556,113,11223468,111333,112347,13557,111223346689,137 %N A243361 a(n) = arrange digits of concatenation of divisors of n (A037278, A176558) in increasing order in base 10 (zero digits are omitted). %C A243361 See A243362 = sequence of numbers n such that a(n) = 123456789: 54023, 54203, 500407, 23456789… First prime in this sequence is 23456789. %e A243361 For n = 20; divisors of 20: 1, 2, 4, 5, 10, 20; a(20) = 112245. %o A243361 (Magma) A243361:=func<n | Seqint(Reverse(Sort(&cat[(Intseq(k)): k in Divisors(n)])))>; [A243361(n): n in [1..100]]; %Y A243361 Cf. A037278, A176558, A243360, A243362, A243363, A243364. %K A243361 nonn,base %O A243361 1,2 %A A243361 _Jaroslav Krizek_, Jun 04 2014